Ferrite rotator devices



May 8, 1962 P. AEGERTER 3,034,080

FERRITE ROTATOR DEVICES Filed Sept. 24, 1959 United States Patent 3,034,080 FERRITE ROTA 0R DEVICES Pierre Aegerter, Paris, France, assignor to Compagnie Generale do Telegraphic sans Fil, a corporation of France Filed Sept. 24, 1959, Ser. No. 842,151 Claims priority, application France Sept. 26, 1958 1 Claim. (Cl. 333--98) The present invention relates to ferrite rotators. Such rotators usually comprise a ferrite element located in a wave guide coaxially therewith and along the axis of which a magnetic field is directed. This field causes the rotation of the polarization plane of the wave propagating in the guide by an angle depending upon the intensity of the field.

Such ferrite gyrator or rotator devices are frequently used in microwave techniques.

For example, ferrite rotators are used in switching arrangements. The magnetic field is caused, in this case, to vary rapidly between two fixed values.

However, the production of such magnetic fields requires the application of substantial amounts of energy.

The present invention has for its object to avoid this drawback.

A ferrite rotator arrangement according to the inven tion comprises at least one ferrite rod located along the axis of a wave guide and two electromagnets positioned in alignment with said ferrite rod, respectively at both ends thereof.

The invention will be best understood from the following description and appended drawing, the single FIG- URE of which represents, very schematically, a rotator according to the invention.

Referring to the drawing, there is shown a circular wave guide 1, wherein a TE wave is propagated. 'iwo ferrite rods 2 and 3 are positioned in the guide coaxially therewith. They are held in position by a flared element 4 made of dielectric material such as Micalex the internal diameter of this element being made smaller at this place, then increasing progressively at the outer ends of rods 2 and 3 thus to insure a better matching of the rods to the guide. The dielectric constant of this element is chosen as known to be equal to the dielectric constant of the ferrite. Two magnets 5 and 6, the length of which is preferably equal to Ag/4X, Ag being the operating wave length, are positioned between the respective outer ends of rods 2 and 3 and the tapered wall portions of element 4.

Coils 7 and 8 are Wound around the guide portions respectively containing magnets 5 and 6. They provide positive or negative pulses for the polarization of mag-.

ice

nets 5 and 6. The induction in the ferrite rods may be adjusted by controlling the gap between rods 2 and 3 and a ceramic element 9 having the same dielectric constant as in such a way that the respective outputs be out of phase by w; In this case positive and negative pulses of equal intensities are alternately fed to both coils 7 and 8, the amplitude of these pulses being selected for alternately creating in magnets 5 and 6 inductions which provide in ferrite rods magnetic fluxes of opposite signs and of the magnitude necessary for rotating the polarization vector y 71" 7! Bind-PI? respectively.

What is claimed is:

A ferrite rotator for rotating the polarization direction of an ultra high frequency wave comprising in combination; a circular wave guide having an axis; an insulating flared element in said Wave guide and having arecess at said axis; a ferrite assembly comprising at least two ferrite rods separated by a gap and extending along said axis, said assembly having two ends; an insulating element in said gap; two magnetic pieces of a ferromagnetic conductive material respectively located at said two ends; and two windings surrounding said pieces for respectively generating polarization fields therein.

References Cited in the file of this patent UNITED STATES PATENTS 2,820,200 (111 Pro Jan. 14, 1958 2,850,705 Chait et a1. Sept. 2, 1953 2,887,664 'Hogan May 19, 1959- FOREIGN PATENTS 1,018,118 Germany Oct. 24, 1957 

